I followed instructions for removing multisite, since DNS issues need to be cleared up with the site's domain name, http://www.site.org vs. site.org, and client decides on whether they will use subdomain or subfolder installation.

At this time, I am simply attempting to access the initial page:
/wp-admin/network.php

Issue: There is no page set-up content beyond the following:

Warning: Please deactivate your plugins before enabling the Network feature.
Once the network is created, you may reactivate your plugins.